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Doctor Drivel
 
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Default Replacing conventional gas boiler v.installing combi


"Late Learner" wrote in message
oups.com...
Please save me from learning life the hard way; I've learnt from past
experiences with plumbers and the like (no offence to honest
professional plumbers) which is why I am turning to you good folks who
selflessly devote time to advising less clued up people like me. I
don't seem to be able to find a trustworthy heating engineer in East
London, so if you know one you can recommend, please kindly pass on the
name and tel.no.

Seems the boiler packed up on New Year's Day. It's a small studio
flat on the third floor. Just before I moved in less than two years
ago, a power shower and new bathroom was installed. I believe the
boiler is very old as it's a Myson Apollo. There could be a number
of reasons why there was suddenly no hot water and replacing the boiler
might seem a bit drastic. I am mindful of costs and have learnt from
past mistakes that a simple problem never has a simple solution and in
the end, the no. of call-outs plus labour and parts equate to paying
for something new upfront.

The hot water was timed to run at certain times of the day, everyday
and circulated the radiators, keeping them lukewarm (I never needed to
turn on the CH) and kept the small flat warm enough. It is wasteful to
heat up a whole cylinder of water just for a shower and washing-up for
1 person. I'm thinking a combi is more suitable in my case.
However, I have to think of the costs of ripping out the conventional
system plus new-ish power shower, hidden pipework,etc.

Would replacing with another conventional boiler be cheaper than
installing a condensing combi system? I am worried about the
condensing plume of steam affecting neighbours in my block of flats. I
also don't have plans to stay in the flat for more than say, 5 years.

Please advise me as to a suitable make and size of boiler. I have
looked at Alpha and Vaillant but seems the heat output is way too much
for a 1-person studio flat but what do I know. How do I calculate the
size of boiler I need? The studio dimensions are 7.5m X 4.37m X 2.62m
( or 24'4" X 14'4" X 8'7.5" ceiling height ).

I would be most grateful for any advice. Thank you.


A combi is ideal for you. You can have non-condensing combis if the plume
is a nuisance. The CH side may appear too large. But they modulate the
burner down so get one that modulates quite low. The hot water? If mainly
showers a 12 litres per min on a 35C temperature rise is adequate if mainly
showers are used. If you take baths all the time then a higher flow is
needed. Make sure the pump is removed from the shower if the combi is fed
from the mains. Have a wall stat/programmer to control the heating. If you
have a cylinder in the studio then the combi will release valuable space.